Not all slack workspace users are a neat set of employees from one organisation. People use Slack for public stuff for example open source. Also private slacks

Not all slack workspace users are a neat set of employees from one organisation. People use Slack for public stuff for example open source. Also private slacks may invite other guests from other companies. And finally the hacker may have accessed an employees account and now has a potential way to get the a root password or other valuable info.